1. Field of the Invention
This invention relates generally to space vehicles, and more particularly relates to a superconductor enclosure for a space vehicle having a magnetic propulsion system.
2. Description of Related Art
Proposals have been made for space vehicles with magnetic propulsion systems, such as for maintaining a spacecraft in orbit, or for launching a space vehicle from the surface of the earth. Such space vehicles would utilize coils or wires attached to the vehicle carrying a current to induce a magnetic field to interact with the earth's own magnetic field, to thereby propel the vehicle. One such proposal involves the use of superconductive material maintained in a temperature region at which superconductivity occurs. Thus, once current flow is established in the coil or loop, current will continue to flow in the superconducting material without requiring additional energy. A cryogenic cooling system may be employed to circulate supercooled fluid such as liquid helium adjacent to the superconductive material. In one proposal for a propulsion system for a space vehicle, interchanges of electromechanical energy with the magnetic field of the earth are used to produce electrical energy for utilization by the space vehicle, and to reduce kinetic energy.
Generally, the principal means of propulsion for such types of vehicles would be magnetic. The magnetic fields can be used for take-off and landing, or hovering at a fixed altitude. Conventional types of solid fuel or liquid fuel boosters may be used for added thrust, or for directional control. Another proposal for boosting thrust or attitude control of a space vehicle within the atmosphere envisions the creation of high electrostatic charges on the surface of the vehicle, on the order of from 25,000 to 1,000,000 volts, by means of an electrostatic generator, although even such large electrostatic charges are generally so weak that they are insufficient for thrust or directional control of a large space vehicle, and would be suitable for only small objects. However, such electrostatic charges may be useful in limited instances for thrust and directional control of a space vehicle, and such charges may be used in a spinning vehicle for communication. Since a spinning charged space vehicle can emit visible radiation, by varying the rate of spin, different frequencies of light might be used for communication, since the magnetic field of the moving space vehicle would be likely to interfere with standard radio communication. Such conventional drive systems and electromechanical and electrostatic systems used in conjunction with a superconducting magnet propulsion system can subject a crew or passengers of the vehicle to high acceleration. To produce the high currents necessary to propel a space vehicle, either a superconducting generator or an ordinary generator charging a bank of superconducting capacitors may be used. Such a magnetic propulsion system using superconducting cables can be expected to generate extremely high magnetic fields of, for example, 10-20 or higher teslas.
In order to protect a crew from the extremely powerful electric and magnetic fields developed in such magnetic and electrostatic systems, it would be desirable to provide such a space vehicle with a protective enclosure that would screen out magnetic and electric fields. It would also be desirable for such an enclosure to protect passengers or crew within the enclosure from acceleration and gravitational forces, preferably in three orthogonal axes.